Machine for the tying of packages

ABSTRACT

A machine for the tying of packages which comprises a tying arm extending above the package and moving around it. An elongated tying element (e.g. cord, tape or wire) is fed to the arm from a supply drum. The tying arm moves around the drum and the tying arm is arranged on a shaft.

United States Patent 1 1 [111 3,880,071

Biittner Apr. 29, 1975 [54] MACHINE FOR THE TYlNG OF PACKAGES 2.471.304 5/1949 Bunn 100/27 X 3.2 3 a 1 )2 [75] Inventor: Hans Hugo Biittner. Mcttmann. 67 8 7 8H9) YO Sm Lt NM 7 Germany [73] Assignee: Firma Buttner Kommandit- Primary E.\wninerBilly Jv Wilhitc gesellschaft Maschinenfabrik, Armrney Agent. or FirmErnest G. Montague; Karl GruiterL Germany F. Ross; Herbert Dubno [22] Filed: May 23. 1973 [21] Appl. No.: 363.270

[57] ABSTRACT [30] Foreign Application Priority Data Ma\' 27. 1972 Germanv .1 22259014 A machine the tying of Packages WhiCh Compriscs l a tying arm extending above the package and moving 52 U.S. c1. .v 100/27 around An ekmgflted fir clement w COM p 51 1111. Cl B6Sb 13/10 Or Wire) is fed to the arm from a pp y drum- The [53] Field of Search 100/27 3 1 53 9 tying arm moves around the drum and the tying arm is arranged on a shaft.

[56] References Cited UNITED STATES PATENTS 4 Claims. 3 Drawing Figures L152,670 9/1915 Thompson 100/28 mmmmwlws 3,880,071 SHEET 10? 3 PATENTEBAPmsms 3,880,071 sum-:1 3 BF 3 FIG. 3 44 27 23 25 MACHINE FOR THE TYING OF PACKAGES The present invention relates to a machine for the tying of packages having a tying arm which extends over the package and moves around it, the tying element or strand being fed to this arm from a supply drum.

In machines, it is known to feed the tying element or strand to the tying arm through the axis of the tying arm. In this way, however, a twisting of the tying means results. This is particularly disadvantageous in the case of a tying element consisting of flat plastic tape. since disturbances in operation can then occur as a result of the twisting.

Machines having a double-arm tying device are also known. The one arm serves for placing the tying element around the package, while the other arm carries the supply drum. Twisting can thus be practically avoided, but increased power is required for the operation of the machine. Furthermore, it is necessary to provide a correspondingly large brake device in order to stop the tying arm after placing of the tying element around the package.

It is one object of the present invention to provide a machine for the tying of packages, which is of simple and designed construction such that the tying element can be placed free of twist around the package without the supply drum having to be seated on the tying arm.

According to the present invention there is provided a machine for the tying of packages, (having a tying arm, which extends above the package and moves around it, to which arm the tying element is fed from a supply drum, the supply arm moving around the tying drum, which is arranged on the shaft of the tying arm).

As a result of this development, there is obtained a machine of simplified construction. The twist-free placing on of the tying element is permitted by the drum which is located on the axis of the tying arm. This is advantageous particularly in the case of a tying element consisting of plastic tape, since disturbances in operation caused by twisting are excluded. Furthermore, there is a reduction in the power required by the arrangement of the drum on the axis of the tying arm because the drum no longer needs to move on a circular path around the axis. This leads to another advantage since, after the completion of the placing of the tie element around the package, less weight need be brought to a stop. The drive/brake device which stops the tying arm can accordingly be made smaller. It has proven to be advantageous, to allow the tying arm to move around the drum in the direction of unwinding of the tying element, since in this way less tensile stress occurs in the tying element. The brake which is coordinated with the supply drum prevents a disturbing continued operation of the drum upon the sudden development of tensile stresses in the tying element. By the aftertensioning device associated with the tying arm, the tensile stresses can be further reduced.

By means of this tensioning device, such an intermediate amount can be stored, that a certain amount of storage is always present, even in the case of large packages. If the tractive force exceeds a predetermined value, the tensioning device brings the brake of the supply drum into a release position. The tensioning device is simple in its construction. It consists essentially of a swing arm arranged on the tying arm and bearing a guide roller on its free end; it is provided with an eccentric on its articulated end. When a certain position of swing is exceeded, the eccentric then actuates the brake which is operatively connected to the supply drum. The brake comprises a jaw brake constructed in such manner, that the eccentric of the swing arm lies between the free sections of the brake jaws. The drum, on the axis of the tying arm, is secured in its attached position indirectly by a vertical wall of the supplementary table. In order to change the drum, the supplementary table can be brought by simple manipulation out of engagement with the axis of the tying arm. In addition to its aforementioned purpose, the supplementary table also serves to support the packages placed on the machine table. The supplementary table and the machine table leave a gap between each other, through which gap the tying element is conducted.

These and other objects will become more readily apparent from the following detailed description, reference being made to the accompanying drawing, in which:

FIG. 1 is an elevation of the machine showing an intermediate position of the tying arm.

FIG. 2 is an elevation of the upper portion of the machine shown on an enlarged scale; and

FIG. 3 is a longitudinal section through the machine drawn to the scale of FIG. 2.

As shown in FIGS. 13, the machine comprises a machine frame 2 provided with legs 1. The machine frame 2 carries the tabletop 3. Within the machine frame 2 there is a drive 4 and a welding unit 5 arranged below the tabletop 3. From the rear wall of the machine frame 2 there extend the two columns 6 which are directed vertically and project above the tabletop 3. At their upper free ends, the columns 6 are connected by a horizontal cross member 7. The latter is provided with a collar 8 welded thereon. Cross member 7 and collar 8 serve to receive the tying-arm shaft 9. For this purpose the tying-arm shaft 9 is provided at its end with a threaded section 10, which serves to receive the threaded nuts I].

The tying-arm shaft 9 has stepped sections l2, l3 and 14. On section 12 there are antifriction bearings 15 on which is mounted the tying arm 16. In the region of the anti-friction bearings 15, the tying arm 16 is provided with a supporting ring 17. The latter is provided on the end facing the cross member 7 with a sprocket wheel 18 on which a chain 18 (FIG. 1) leading to the drive 4 acts. Via this sprocket wheel 18, the tying arm 16 can be swung around the shaft 9 of the tying arm.

The stepped section 13 supports the bushing 20 by means of the antifriction bearings 19. At the end thereof facing the section 12, a disk 21 is welded. The said bushing receives the sleeve 22 of the supply drum 23.

A recess 24 is provided in the free end of the bushing 20. In the recess 24 there is guided a pot-shaped bushing 25. The edge 25' of the pot bears at its end a supporting disk 26 for the supply drum 23, while the bottom 25" of the pot is acted on via an antifriction bearing 27 by a compression spring 28. This compression spring 28 rests against a collar 30 of a bushing section 33 rigidly connected with the vertical wall 31 of the supplementary table 32.

For the mounting of the bushing section 33 on the stepped section 14 there is employed a sliding bolt 34 the fork tines 34' of which extend over flattened portions 14 lying parallel to each other of the stepped section 14. The flattened portions 14' are so large that they permit a slight axial displacement of the bushing section 33 on the stepped section 14 in the direction indicated by the arrow .r. The bushing section 33, however, is always held in the one end position by means of the compression spring 28. At the other end, the compression spring 28 provides, via the pot-shaped bushing and supporting disk 26, an axially nondisplaceable seat for the supply drum 33 on the bushing 20.

For the fastening of the sliding bolt 34 there is pro vided a lock screw 35 which passes through a longitudi nal slot 36 in the bolt 34. The lock screw 35 extends from the vertical wall 31 of the supplementary table 32. By this arrangement the supplementary table is secured against swinging, since it is in form-locked engagement with the shaft 9 via the bolt 34.

For the changing of the tie supply drum, the lock screw 35 must be loosened. The bolt 34 must then be shifted in the direction indicated by the arrow y in such a manner that the tines 34' of the bolt 34 move back completely from the flattened portions 14' of the stepped section 14. Thereupon the supplementary table 32 together with the bushing section 33 and the pot-shaped bushing 25 and support disk 26 can be withdrawn from the shaft 9 of the tying arm. In order to facilitate this withdrawal of the supplementary table 32. the end supporting surface 32' of the supplementary table 32 is swingable around the hinge 29 into the position shown in dot-dash lines in H6. 3. After the insertion of a new supply drum 23, the above-mentioned parts are again brought into the position shown in the drawing.

The tying arm 16 moves around the drum 23 in the direction indicated by the arrow 1. This direction corresponds to the direction of unwinding of the tying ele ments.

The tying arm 16 is angular. It consists of the two angle legs 16 and 16". The leg 16' provided with the supporting ring 17 is provided with a bearing pin 37. On it there is seated a single-armed swing arm 38 as well as an eccentric 39. Eccentric 39 and swing arm 38 are rigidly connected with each other. The swing arm 38 is under the action of a torsion spring 40 which urges the swing arm in the direction indicated by the arrow u.

The end position of the swing arm 38 is limited when the radially protruding sections 39' of the eccentric 39 strike against the corresponding pin-like stops 41 of the tying arm 16 (See FIG. 2).

The eccentric 39 extends between two paralleldirected sections 42 of the brake jaws 43. The latter are supported on the side of the tying-arm shaft 9 opposite the eccentric 39 on corresponding pins 44 of the tying arm 16. In the position shown in FIG. 2, the brake jaws 43 rest against the outer surface of the brake ring 45 which is connected in suitable manner with the disk 21. This brake position is maintained by a tension spring 46 which extends between the parallel-directed sections 42 of the brake jaws 43.

The swing arm 38 at its free end bears the tyingmeans guide roller 47.

The angle leg 16' of the tying arm 16 bears a guide roller 48 which lies on the same plane as the tyingmeans guide roller 47.

On the angle leg 16", the further guide rollers 49, 50 and 51 which lie in relatively staggered planes are rotatably supported. The guide rollers 50 and 51 are seated on an end angle piece 52 of the leg 16".

The tying element pulled off from the tyingmeans drum 23 is placed in the path indicated by the arrow over the guide rollers 49-51. The tying element is a flat plastic tape guided so that the element leaving the guide roller 51 rests with its wide surface parallel to the surface of the package and in this way permits a twistfree placing of the tying element around the package. In order to make it possible to bring the tying means around the package. there is a gap 53 between the supplementary table 32 and the machine table 3.

The tying proceeds as follows: in FIG. 1 there is shown in dot-dash lines the starting position of the tying arm 16. In this position the swing arm 38 which forms the after-tensioning device has stored an unwound intermediate supply. The end of the tying means is located, in accordance with the starting position, in a clamp 54 of the welding unit 5. After a complete movement of the tying arm 16 around the package, the tying arm then again assumes the position shown in dot-dash lines in FIG. 1. Due to the tensile stresses occuring upon the tying of the package, the swing arm 38 can move in opposition to the direction in which it is urged by its spring. After exceeding a certain position of swing, the eccentric 39 strikes the sections 42 of the brake jaws 43 which in their turn move away from the outer surface of the brake ring 45 and permit rotation of the tying-means drum 23. In this way, excessively large withdrawal tensions in the tying means are excluded. After the tying means have been placed in this manner around the package, the ends of the tying means can be tied and the tying means cut, but in such a manner that the end of the tying means is held by the clamp 54.

1 claim:

1. An apparatus for tying a package by slinging a tying element therearound, said apparatus comprising;

a support for a package to be tied;

a tying arm swingably mounted on said support for slinging said element about said package from an end of said arm;

means defining a swing axis for said arm on said support;

a supply drum mounted on said support with its axis coinciding with said swing axis for feeding said element to said arm;

a brake limiting rotation of said supply drum;

an after-tension device on said arm retaining and unwound length of said element thereon intermediate said drum and said end of said arm; and

means operatively connecting said device with said drum for controlling said brake in response to the tension of said element at said device.

2. The apparatus defined in claim 1 wherein said device comprises a swing arm pivotally mounted on said tying arm; spring means biasing said swing arm relative to said tying arm in one direction, a guide roller on a free end of said swing arm and engaging said element, and eccentric means operated by said swing arm and connected to said brake.

3. The apparatus defined in claim 2 wherein said brake comprises a pair of jaws, said eccentric means being positioned to spread said jaws.

4. The apparatus defined in claim 1 wherein said tying arm is mounted upon a fixed shaft, said apparatus further comprising a table detachably mounted on said shaft; and means for locking said table to said shaft against swinging. 

1. An apparatus for tying a package by slinging a tying element therearound, said apparatus comprising; a support for a package to be tied; a tying arm swingably mounted on said support for slinging said element about said package from an end of said arm; means defining a swing axis for said arm on said support; a supply drum mounted on said support with its axis coinciding with said swing axis for feeding said element to said arm; a brake limiting rotation of said supply drum; an after-tension device on said arm retaining and unwound length of said element thereon intermediate said drum and said end of said arm; and means operatively connecting said device with said drum for controlling said brake in response to the tension of said element at said device.
 2. The apparatus defined in claim 1 wherein said device comprises a swing arm pivotally mounted on said tying arm; spring means biasing said swing arm relative to said tying arm in one direction, a guide roller on a free end of said swing arm and engaging said element, and eccentric means operated by said swing arm and connected to said brake.
 3. The apparatus defined in claim 2 wherein said brake comprises a pair of jaws, said eccentric means being positioned to spread said jaws.
 4. The apparatus defined in claim 1 wherein said tying arm is mounted upon a fixed shaft, said apparatus further comprising a table detachably mounted on said shaft; and means for locking said table to said shaft against swinging. 